Reader Mark Basiliere from the South Shore drives a car pool of friends to the Financial District, stopping mornings at the top of Boston’s Lincoln Street, parking in Fort Point Channel, and picking up in the evening opposite 245 Summer St., near South Station, which he says has become nightmarish.

“It is amazing to me that daily multiple cabs pull over right after they turn from Atlantic onto Summer Street to drop off and pick up passengers, blocking one full lane,” Basiliere wrote. “This causes the drivers going up Summer Street to merge into one lane, resulting in backups. Throw a truck trying to turn right onto Summer from Atlantic, and it becomes a cluster ‘bleep.’ ”

It’s hairier in the afternoon, with train commuters running toward the station, cabs pulling over indiscriminately, and bike riders eschewing road rules — causing Summer-Atlantic gridlock that is exacerbated by what Basiliere says is a mismatched traffic light and walk signal at Surface and Summer streets, causing conflict between cars and pedestrians.

Good news. James Mansfield of the Boston Transportation Department says Basiliere’s mostly right. Part of Atlantic is reserved for taxis and part is marked no stopping/standing, patrolled routinely by city parking officers. Increasingly, cabs have been using the commercial vehicle parking along Summer as well, Mansfield said, which is technically allowed. But double-parking by taxis is becoming more common, and the city will increase enforcement, he said.

As for gridlock, blocking an intersection is illegal, subject to a $150 fine. The city reviewed the signals at that intersection and found the timing to be correct, though it is programmed for a “concurrent walk,” meaning it tells pedestrians to go while also allowing right turns — with motorists supposed to know that pedestrians have the right of way.

“To help mitigate the issues the writer has experienced, we have asked that our parking officers make additional sweeps of the area to move double and other illegally parked vehicles from the area,” he said.